a. Field of the Invention
The present invention relates to a process of catalytic steam reforming of hydrocarbons having at least 2 carbon atoms per molecule at a temperature in the range of 300.degree. to 600.degree. C, and to be more precise, it relates to a process of manufacturing a methane-containing gas -- particularly a methane-rich gas -- by, for instance, adiabatically steam reforming feed hydrocarbon(s) in the presence of an improved ternary catalyst comprising a nickel component and a magnesia component supported on a carrier (hereinafter called 'a nickel-magnesia-carrier catalyst' for short) which is capable of demonstrating superior effects in the low-temperature steam reforming reaction.
B. Description of the Prior Art
There have hitherto been proposed a variety of processes of manufacturing a methane-containing gas by subjecting feed hydrocarbon(s) to a low-temperature steam reforming reaction in the presence of a nickel catalyst. To cite instances, there are Japanese Patent Publication No. 11047/1965 teaching the employment of a catalyst consisting of nickel-alumina-lanthanide rare earth, Japanese Patent Publication No. 11048/1965 teaching the employment of a catalyst consisting of nickel-alumina-iron, Japanese Patent Publication No. 19174/1970 teaching the employment of a catalyst consisting of nickel-alumina-alkaline earth metal, and so on.
However, the employment of these conventional catalysts in performing low-temperature steam reforming reaction over a long period of time -- particularly a low-temperature steam reforming reaction under the condition of high pressure -- has shown a tendency to develop some instable factors such as deterioration of the catalyst, per se, or deposition of carbonaceous matters on the catalyst, etc.